Abstract

A confluence of developments across a range of subfields --- particularly experimental advances in building Noisy Intermediate-Scale Quantum (NISQ) devices --- have opened up a vast new territory of studying many-body phenomena in completely novel regimes: highly excited, "post Hamiltonian", and far from equilibrium. NISQ devices, while still far from achieving fault-tolerant quantum computation, are exceptional laboratory systems, with large many-body Hilbert spaces and unprecedented capabilities for control and measurement. The natural evolutions implemented by these novel experiments are dynamics generated by quantum circuits of unitary gates, possibly interrupted by measurements, and starting from initial states that are not low energy in any useful sense. These platforms present an opportunity to explore vastly larger tracts of Hilbert space that are normally hard to reach and motivate new paradigms of phase structure. They also present new ways to interrogate a quantum system to probe complex quantum correlations, for instance, via an interactive dialog with a classical experimenter. I will describe some highlights of an active research program to advance many-body theory beyond the regime of near-equilibrium time-independent Hamiltonians, with a view towards uncovering novel emergent phenomena in the non-equilibrium dynamics of many-body systems and the physics of (possibly interactive) quantum circuits.

Bio

Vedika Khemani is an assistant professor of physics at Stanford University. After completing her Ph.D. at Princeton in 2016, she did her postdoctoral work as a Junior Fellow at Harvard. She is a recipient of an Alfred P. Sloan Fellowship, the William L. McMillan Award, the APS George E. Valley Jr. Prize, the Breakthrough New Horizons in Physics Prize, and a Packard Fellowship in Science and Engineering.